Recently, data communication using a communication apparatus has been performed in a variety of fields. Data communication can be classified into various types according to communication types. For example, when two-way data communication is performed between a first communication apparatus and a second communication apparatus, the first communication apparatus can transmit data to the second communication apparatus, and the second communication apparatus can also transmit data to the first communication apparatus. In other words, when two-way data communication is performed, the two communication apparatuses can exchange data.
On the other hand, when one-way data communication is performed between a first communication apparatus and a second communication apparatus, the first communication apparatus can transmit data to the second communication apparatus, but the second communication apparatus cannot transmit data to the first communication apparatus. In other words, when one-way data communication is performed, since the first communication apparatus operates as a transmission apparatus and the second communication apparatus operates as a reception apparatus, data can be transmitted in only one direction.
A communication apparatus can receive data from another communication apparatus and determine whether there is an error in the received data. Here, there may be an error in the received data. When two-way data communication is performed, the communication apparatus can notify the other communication apparatus of the data error and transfer information on the data error. However, when one-way data communication is performed, the reception apparatus cannot transfer information on the data error to the transmission apparatus. This is because data is transmitted in only one direction.
To solve this problem in one-way data communication, several methods have been proposed. As an example, a method in which a transmission apparatus adds information that can be used for self error recovery to data and transmits the data to a reception apparatus, and when there is an error in the received data, the reception apparatus performs self error recovery with reference to the added information has been proposed. However, according to this method, it takes a long time to encode and decode information used for self error recovery, and data may be unnecessarily duplicated. Further, an error deviating from a range in which self error recovery is possible cannot be corrected.
As another example, a method in which a separate communication link is added between a transmission apparatus and a reception apparatus to transfer a result of detecting a data error from the reception apparatus to the transmission apparatus has been proposed. However, according to this method, the communication link is used in a reverse direction with respect to a communication link used for one-way data communication. Therefore, characteristics of one-way data communication deteriorate.